Answer:
Radius of the solenoid is 0.93 meters.
Explanation:
It is given that,
The magnetic field strength within the solenoid is given by the equation,
, t is time in seconds

The induced electric field outside the solenoid is 1.1 V/m at a distance of 2.0 m from the axis of the solenoid, x = 2 m
The electric field due to changing magnetic field is given by :

x is the distance from the axis of the solenoid
, r is the radius of the solenoid


r = 0.93 meters
So, the radius of the solenoid is 0.93 meters. Hence, this is the required solution.
Answer:
n (a neutron)
Explanation:
For a chemical element:
- The lower subscript indicates the atomic number (the number of protons)
- The upper subscript indicates the mass number (the sum of protons and neutrons in the nucleus)
In the reaction described in the problem, we see that a gamma photon hits a nucleus of Calcium-40, which has
Z = 20 (20 protons)
A = 40 (40 protons+neutrons)
Which means that the number of neutrons is n = A - Z = 40 - 20 = 20
After the reaction, we have a nucleus of Calcium-39, which has
Z = 20 (20 protons)
A = 39 (39 protons+neutrons)
Which means that the number of neutrons is n = A - Z = 40 - 39 = 19
So, the nucleus has lost 1 neutron, which is the particle missing in the reaction.
Answer: There will be 75258 nuclei left at 6 pm.
Explanation:
a) half-life of the radioactive substance:
Half life is the amount of time taken by a radioactive material to decay to half of its original value.


b) Expression for rate law for first order kinetics is given by:

where,
k = rate constant
t = time for decomposition = 6 hours ( from 12 noon to 6 pm)
A = activity at time t = ?
= initial activity = 600, 000


Thus there will be 75258 nuclei left at 6 pm.
Answer:
he maximum frequency occurs when the denominator is minimum
f’= f₀ 
Explanation:
This is a doppler effect exercise, where the sound source is moving
f = fo
when the source moves towards the observer
f ’=f_o
Alexandrian source of the observer
the maximum frequency occurs when the denominator is minimum, for both it is the point of maximum approach of the two objects
f’= f₀ 
First of all, we can find the mass of the person, since we know his weight W:

And so

We know for Newton's second law that the resultant of the forces acting on the person must be equal to the product between the mass and the acceleration a of the person itself:

There are only two forces acting on the person: his weight W (downward) and the vincular reaction Rv of the floor against the body (upward). So we can rewrite the previous equation as

We know the acceleration of the system,

(upward, so with same sign of Rv), so we can solve to find the value of Rv, the normal force exerted by the elevator's floor on the person: